1. Hilton Head Island, South Carolina Draper Laboratory, Cambridge, MA
The Precision Airdrop System (PADS) Airborne Mission Planner: A System Now Enabling Precision High Altitude Airdrop
Presented at the Aerospace Control and Guidance Systems Committee Meeting
Hilton Head Island, South Carolina
by Phil Hattis
Draper Laboratory, Cambridge, MA
October 21, 2005

2. Outline PADS objectives and architecture
Current Precision Airdrop Planning System (PAPS) capabilities
PADS features used by PAPS
Demonstrated performance
Deployment status and next development steps
Summary

3. PADS Objectives and Architecture
System Objectives
Overarching Goals
Enable precision cargo delivery from high altitude
Combat re-supply
Humanitarian relief
Reduce surface weapon threats to carrier aircraft
Enable delivery aircraft to remain near their upper altitude limit for airdrop
Specific PADS Goals
Provide a common platform for ground-based and in-flight airdrop Mission Planning (MP)
Enable application to ballistic and guided airdrop systems
Support both cargo and personnel drops
Include advanced wind modeling
Make the planning system easy to use and its outputs easy to understand

4. Some Mandated PADS Features
PADS Objectives and Architecture
Some Mandated PADS Features
Compatibility with C-130 and C-17 carrier aircraft
Computed Air Release Point (CARP) determination on board carrier aircraft
Generation of expected delivery footprints (for nominal airdrops and major failure scenarios)
PADS “snap-on/snap-off” capability on the carrier aircraft
Means to receive wind and mission updates while in transit to the Drop Zone (DZ)
Wireless updates of guided airdrop system mission plans while in transit to the DZ
The look and feel of the Portable Flight Planning System (PFPS)
Easy to understand MP outputs, including data displays over maps or images

5. PADS Software Components
PADS Objectives and Architecture
PADS Software Components
A laptop personal computer (PC) with the following features
The “WindPADS” atmosphere modeling tool provided by Planning Systems, Inc. (PSI)
A PAPS that accounts for:
Payload weight, aircraft load station, decelerator type
Altitude, heading, and airspeed at release
Roll-out and decelerator opening models (for ballistic parachutes)
6 degree of freedom (6 DOF) cargo/decelerator descent models
A tool to predict the expected payload delivery footprints
Means to acquire real-time aircraft state data
An easy-to-use PFPS-like Graphical User Interface (GUI)
A image/map overly display using FalconView including:
Desired CARP, and feasible release envelopes for guided airdrops
Expected landing footprints (for ballistic parachutes) and expected impact footprints for failed airdrop systems

6. PSI-Supplied PADS Block 2 Flight Hardware Components
PADS Objectives and Architecture
PSI-Supplied PADS Block 2 Flight Hardware Components
Key Components
(clockwise from upper-left)
Panasonic CF-29 data processor with g wireless interface
4-channel UHF radio transmitter
Cables and connectors to aircraft interface
GPS hand-launched dropsonde (expendable)
Total weight with portable
case: 75 pounds
This page extracted from AIAA paper CP , “On-Board Atmospheric Modeling System to Support Precision Airdrop,” by R. Wright, R. Benney, and J. McHugh, presented at the Conference, Arlington, Virginia, September 26-29, 2005

7. PADS System Features and Interfaces
PADS Objectives and Architecture
PADS System Features and Interfaces
Wind Data Sources
Satellite-Derived
TACMET Radiosonde
Theater Pilot Reports
Com Satellite
Air Force Weather Agency Atmospheric Forecast Model - High-Resolution Nested Grid Surrounding Drop Zone(s)
5-KM Grid Domain within 15-KM Grid Domain
Combat Track II
Radio Receiver
Aircraft Top Antenna
INTERNET/SIPRNET
Secure Interface
Laptop Computer
Guided/SmartAirdrop Systems
Mesoscale 4D Field
Assimilation Processor
PIP
GPS Dropsonde
Dropsonde Processor
3D Field - Wind, Density, Pressure for Drop Time
Airdrop DynamicsSimulation
Via G Wireless
Radio Receiver
PADS-Derived Upload Data
Aircraft Bottom Antenna
Computed Air Release Point (CARP)
Navigator or Navigation System
Aircraft 1553 Data Bus

8. Ballistic Parachute Support
Current PAPS Capabilities
Ballistic Parachute Support
MP support for an expandable set of systems, currently including:
G-12 and 26 ft ring-slot hemispherical canopy airdrop systems
Enables delivery of payloads in the 2,000 lb class (+/- 25%)
Includes treatment of stick releases (multiple load drops on a single pass)
Targets the stick’s CARP for any one designated load in a stick
Determines expected delivery footprints for each load in a stick
Footprint determination for the Tri-wall Aerial Delivery System (TRIADS)
Enables airdrop of Meals Ready to Eat (MREs)
MP parachute trajectory determination accounts for:
Aircraft release and roll-out dynamics
Canopy opening and deceleration
Descent response to 3D wind and density fields
Statistical variation in all the above effects
TRIADS trajectory determination accounts for:
Carrier box release and deceleration dynamics
Dispersed MRE statistical response to 3D wind and density fields

9. Airdrop Trajectory Factors Treated by PAPS
Current PAPS Capabilities
Airdrop Trajectory Factors Treated by PAPS

10. Guided Airdrop Support
Current PAPS Capabilities
Guided Airdrop Support
Supports an expandable set of cargo airdrop systems, with L/D values ranging from 0.5 to over 4, currently including:
Sherpa, Screamer, and the Affordable Guided Airdrop System (AGAS) in the 2,000 lb payload class
Screamer and Dragonfly in the 10,000 lb payload class
Seeing initial application to personnel airdrops
MJN-1, MC-4/5 and variants, as well as a generic canopy capability
Derives feasible release zones and preferred CARPS, including for sticks with varied landing targets
MP trajectory determination accounts for:
System-specific L/D and velocity vs. payload mass characteristics
Descent response to 3D wind and density fields
Dispersion footprints generated for the following scenarios:
Failed canopies
Failed guidance and/or control after successful canopy deployment

11. Feasible Release Cone Determination: Single Load
Current PAPS Capabilities
Feasible Release Cone Determination: Single Load
Feasible Release Code Without Wind Correction
Release Cone Correction Due to Wind Effects

12. Feasible Release Cone Determination: Stick Loads
Current PAPS Capabilities
Feasible Release Cone Determination: Stick Loads
Illustrated for two loads without wind effects
MP can handle multiple load sticks
Wind and density effects on all cones assessed before identifying feasible release envelope

13. Interface Functionality
PADS Features Used by PAPS
Interface Functionality
Graphical User Interfaces (GUIs)
Modeled after PFPS Combat Airdrop Planning Software (CAPS) GUIs
Accommodates user inputs of payload data before flight
Carrier aircraft type; payload mass; cargo bay location; airdrop system type; DZ target; planned release altitude and airspeed; expected weather data source file; etc.
Provides resulting CARP and engineering data displays
FalconView Overlay Displays
Provides visual user cues regarding:
CARP locations; landing footprints; feasible release zones; etc.
1553 Bus Interface
Provides aircraft navigation data and at-altitude wind estimate
Enables monitoring designated bus data
Combat Track II CTII Interface
Provides secure UHF-link access to flight plan and wind updates during transit to the DZ
File Upload Capability
Provides an in-transit wireless interface for upload of updated descent mission plans for guided airdrop systems

14. Some PADS GUIs Used by PAPS
PADS Features Used by PAPS
Some PADS GUIs Used by PAPS
CARP Solution Data
Cargo Bay Coordinates
CARP Solution Status Indicator
Payload Locations In Cargo Bay
Top-Level PADS GUI Page Provides Tabbed Data Summaries and Access to all MP functionality
Load & Chute GUI Enables User Input of Payload Data and Displays Resulting Payload Layout in the Cargo Bay

15. Example PAPS FalconView Image and Map Overlay Displays
PADS Features Used by PAPS
Example PAPS FalconView Image and Map Overlay Displays
Guidance Failure Footprints
Planned Impact Points
Run In
Nominal Descent Dispersion Footprints
CARP
CARP
Failed Canopy Dispersion Footprints
Individual Release Envelopes
Ballistic Parachute Nominal and Failure Footprint Displays
Guided Airdrop System Release Envelopes and Failure Footprints

16. Ballistic Parachute Operational Utility Evaluation (OUE) Results
Demonstrated Performance
Ballistic Parachute Operational Utility Evaluation (OUE) Results
C-130 Results
C-17 Results
Carrier Aircraft Mission Computer Expected Results Using Pre-Flight Wind Data
C-130: 595 m
C:17: m
Carrier Aircraft Mission Computer Expected Results Using PADS-Derived Wind Data
C-130: 492 m
C-17: 486 m
PADS MP Directed Airdrop Results
C-130: 260 m
C-17: 308 m
OUEs involved dozens of 4-payload stick drops using 26 ft ring-slot parachutes accomplished over 2 weeks
Missions were executed by regular Air Force flight crews given 1 day of PADS training
Drops were a mix of releases from 18,000 and 25,000 ft
Accuracy scoring was based on the designated CARP payload in each stick

17. Guided Airdrop System Demonstration Status
Demonstrated Performance
Guided Airdrop System Demonstration Status
Numerous guided airdrop system flight tests have been accomplished using PADS-generated mission update files uploaded in transit to the DZ
Sherpa, AGAS and Screamer 2,000-lb class systems
Dragonfly 10,000-lb class systems
All the 2,000-lb class systems have achieved mean accuracies better than 100 m to their targets, including stick releases with scattered targets
Despite the still early developmental status of its guidance and control system, the Dragonfly has achieved mean accuracies of about 200 m using PADS generated mission files

18. Deployment Status and Next Development Steps
PADS is now in initial field use
Some military free fall operations now apply PADS to assure personnel jumps from carrier aircraft are within reach of the DZ
2,000 pound-class guided airdrop systems are currently being fielded with PADS MP support capability enabled
PADS-enabled precision ballistic parachute and guided airdrop system delivery capabilities to be used to limit the need for hazardous ground convoys in many scenarios
Initial PADS MP support capabilities for 10,000 and 30,000 pound class guided and ballistic parachute airdrop systems will be available for field use by the end of the calendar year
An open architecture Guidance, Navigation, and Control (GN&C) software package for steerable parafoil applications to be hosted on PADS laptops is under development
Will be available for upload to compatible guided airdrop systems
Designed to provide GN&C for a wide variety of parafoil airdrop systems

19. Summary
A Precision Airdrop System (PADS) in-flight Mission Planner (MP) has completed initial development and is now being used in the field
Applies high fidelity wind estimates based on data gathered from forecast, in situ measurements, and securely transmitted data
Supports ballistic parachute and guided system airdrops of cargo and personnel
Has interfaces compatible with the Portable Flight Planning System to assure ease of use by carrier aircraft crew in the field
Operation Utility Evaluation from C-130 and C-17 aircraft was completed for ballistic parachute airdrops
Major accuracy improvement was demonstrated in comparison to prior high altitude airdrop methods
The fielded PADS MP supports a variety of 2,000 pound class airdrop systems
Provides mission plan upload capability for guided airdrop systems
An extension of the PADS MP to 10,000 and 30,000 pound class airdrops systems is currently in work